Torque Converter
Convert between different torque units including newton-meters, pound-force feet, and more
Newton-meters ⟷ Pound-force feet
1 N·m = 0.7376 lbf·ft
1 lbf·ft = 1.356 N·m
Kilogram-force meters ⟷ Newton-meters
1 kgf·m = 9.807 N·m
1 N·m = 0.102 kgf·m
Pound-force inches ⟷ Newton-meters
1 lbf·in = 0.113 N·m
1 N·m = 8.851 lbf·in
Understanding Torque Measurement Systems
Torque measures rotational force around an axis, calculated as Force × Distance from the axis. Different unit systems serve specific engineering applications: SI units (Newton-meters) for international standards, Imperial units (pound-force feet) for US mechanical engineering, and specialized systems for precision applications.
The Fundamental Concept
Torque = Force × Distance (τ = F × r)
This relationship establishes torque as the rotational equivalent of linear force. Understanding this principle is essential for machinery design, fastener specifications, and rotational system analysis.
Core Conversion Formulas
• 1 Newton-meter [N·m] = 0.7376 pound-force feet = 8.851 pound-force inches
• 1 pound-force foot [lbf·ft] = 1.356 Newton-meters = 12 pound-force inches
• 1 kilogram-force meter [kgf·m] = 9.807 Newton-meters = 7.233 pound-force feet
• 1 dyne-centimeter [dyn·cm] = 10⁻⁷ Newton-meters = 7.376×10⁻⁸ pound-force feet
Reference Torque Standards
• Small screws (M3): 0.5-1.2 N·m
• Automotive lug nuts: 80-140 N·m (60-100 lbf·ft)
• Bicycle pedaling: 40-80 N·m
• Car engine peak torque: 200-600 N·m
• Industrial motor torque: 1-10000 N·m
Automotive Engineering
- • Engine torque specifications and performance curves
- • Wheel lug nut tightening specifications
- • Transmission and differential design calculations
- • Brake system torque requirements and analysis
- • Steering system force and feedback calculations
Mechanical Engineering
- • Fastener torque specifications and joint integrity
- • Motor and gearbox selection and sizing
- • Coupling design and power transmission systems
- • Machine tool spindle torque and cutting forces
- • Assembly line torque tool calibration and control
Aerospace & Defense
- • Aircraft control surface actuator requirements
- • Spacecraft reaction wheel and gyroscope systems
- • Helicopter rotor and transmission torque analysis
- • Missile guidance system precision torque motors
- • Satellite attitude control and stabilization systems
Hand Tools & Small Fasteners
• Watch screws: 0.001-0.01 N·m
• Electronics screws: 0.1-2 N·m
• Hand screwdriver: 1-10 N·m
• Manual wrench: 10-100 N·m
• Impact wrench: 100-1000 N·m
Automotive Applications
• Spark plugs: 20-30 N·m
• Oil drain plug: 25-45 N·m
• Wheel lug nuts: 80-140 N·m
• Cylinder head bolts: 100-200 N·m
• Engine crankshaft: 200-600 N·m peak torque
Industrial Machinery
• Small electric motors: 1-100 N·m
• Industrial gearboxes: 100-10,000 N·m
• Large pumps: 1,000-50,000 N·m
• Wind turbines: 10,000-500,000 N·m
• Ship propulsion: 100,000-2,000,000 N·m
Precision Instruments
• Optical mounts: 0.01-1 N·m
• Laboratory equipment: 0.1-10 N·m
• Medical devices: 0.001-5 N·m
• Scientific instruments: 0.01-50 N·m
• Measurement devices: 0.001-10 N·m
Over-torque Protection Systems
Clutches, shear pins, and electronic limiters prevent damage from excessive torque. Critical for equipment protection and operator safety.
Torque Safety Factors
Design margins for dynamic loads, impact forces, and operating condition variations. Ensures reliable operation throughout equipment lifecycle.
Failure Mode Analysis
Understanding how excessive torque causes component failure. Important for design validation and preventive maintenance programs.
Operator Safety Protocols
Proper torque tool usage, PPE requirements, and safety procedures for high-torque applications in industrial environments.
What's the difference between torque and power?
Torque is rotational force (N·m), while power is the rate of energy transfer (Watts). Power = Torque × Angular Velocity, so high torque at low speed can equal high power at low torque.
Why do torque specifications vary for the same fastener?
Torque requirements depend on material, thread lubrication, surface finish, and environmental conditions. Specifications account for these variables to ensure proper clamping force.
How accurate should torque measurements be?
Accuracy requirements vary by application: critical safety fasteners need ±3-5%, general assembly accepts ±10-15%, and rough applications may allow ±25%.
What causes torque wrench calibration drift?
Regular use, dropping, exposure to extreme temperatures, and age affect calibration. Professional torque wrenches should be calibrated annually or per manufacturer specifications.
How do I convert between different torque units?
Use consistent conversion factors: 1 N·m = 0.7376 lbf·ft = 8.851 lbf·in. Always verify critical calculations and consider the precision requirements of your application.